The digestive efficiency of two forms of enteric-coated pancrelipase, Cotazym-STM and Pancrease, was compared in three boys and three girls, aged 12 through 15, with cystic fibrosis. Each patient served as his or her own control, taking one type of pancrelipase for half of the two-week study and the other type for the second half of the study. Monitoring of the patients' oral intake (calories, protein, fat, carbohydrate), collection and analysis of their stools (volume, nitrogen, fat, fat loss, protein loss), and tests of their urine (creatinine, uric acid), blood (24 determinations), and pulmonary function revealed no significant differences in any of the measures between patients taking Cotazym-S and those taking Pancrease.